diff --git a/platformio/exception.py b/platformio/exception.py
index 5b30ba24..6d3a7641 100644
--- a/platformio/exception.py
+++ b/platformio/exception.py
@@ -45,7 +45,7 @@ class UnknownPlatform(PlatformioException):
 class PlatformNotInstalledYet(PlatformioException):
 
     MESSAGE = "The platform '{0}' has not been installed yet. "\
-        "Use `platformio platforms install {0}` command"
+        "Use `platformio platform install {0}` command"
 
 
 class BoardNotDefined(PlatformioException):
diff --git a/platformio/managers/platform.py b/platformio/managers/platform.py
index ce37665c..fb53d255 100644
--- a/platformio/managers/platform.py
+++ b/platformio/managers/platform.py
@@ -496,7 +496,10 @@ class PlatformBoardConfig(object):
             self._manifest = util.load_json(manifest_path)
         except ValueError:
             raise exception.InvalidBoardManifest(manifest_path)
-        assert set(["name", "url", "vendor"]) <= set(self._manifest.keys())
+        if not set(["name", "url", "vendor"]) <= set(self._manifest.keys()):
+            raise exception.PlatformioException(
+                "Please specify name, url and vendor fields for " +
+                manifest_path)
 
     def get(self, path, default=None):
         try: